“What we want to do – and want to get over – is how society needs to move from thinking about HIV as positive or negative and thinking about HIV as a death sentence, to thinking about whether they’re infectious or not infectious.”

She said that people with HIV “are leading lives that are normal in quality and length. With effective treatment, they are not infectious”.

The move has been welcomed by groups who campaign on issues surrounding Aids and HIV.

About 100,000 people in the UK are living with HIV, although experts say a quarter of those who are infected do not know they have it. In 2011, there were around 6,000 new diagnoses of HIV in the UK.

Under the new rules, health care workers with HIV will be allowed to undertake all procedures if they are on effective combination antiretroviral drug therapy.

They must also have an undetectable viral load of HIV in their system, and must be regularly monitored.

There have been four cases worldwide of health workers infecting patients, with no cases in the UK, and the Government predicts that patients will have more chance of being struck by lightning than being infected with HIV by a health worker.

Around half of HIV infections are currently discovered late, which can make them difficult to treat. Under the changes, health workers will be monitored every three months by the person treating them and by occupational health professionals.

Around 110 staff currently working in the NHS, including doctors and midwives, are covered by the current regulations, Prof Davies said.

NHS workers are tested for HIV at the start of their career, while anyone starting a job that could expose patients to potential risk is also tested.

Staff are obliged under professional codes of conduct to have a further test if they think they may have been exposed to HIV, although this is not legally enforced.

Public Health England, the executive agency of the Department of Health, will set up a confidential register holding data on infected workers, including on their viral load and treatment.

Prof Davies said: “Many of the UK’s HIV policies were designed to combat the perceived threat at the height of HIV concerns in the 1980s and have now been left behind by scientific advances and effective treatments.

“It is time we changed these outdated rules which are sometimes counterproductive and limit people’s choices on how to get tested or treated early for HIV.

“What we need is a simpler system that continues to protect the public through encouraging people to get tested for HIV as early as possible and that does not hold back some of our best health care workers because of a risk that is more remote than being struck by lightning. The risk is absolutely negligible, we are talking about people being treated so they are not infectious.”

She added that self-testing kits must comply with EU rules. If a test is positive, people will be advised to have a follow-up test at an NHS clinic to confirm the results.

Professor Damien Walmsley, scientific adviser to the British Dental Association, said the change in policy brought the UK in line with many other countries.

“Dentists in the UK comply with rigorous infection control procedures to protect both patients and the dental team against the risk of transmission of blood-borne infections,” he added.

Deborah Jack, chief executive of the National Aids Trust (NAT), welcomed the new policy, stating: “Allowing health care workers living with HIV to undertake exposure-prone procedures corrects the current guidance which offers no more protection for the general public but keeps qualified and skilled people from working in the career they had spent many years training for.”

Sir Nick Partridge, chief executive at Terrence Higgins Trust, said: “So long as the right safeguards are in place, there is now no reason why a dentist or a midwife with HIV should be barred from treating patients. We hope these changes continue to improve public understanding of HIV and support for those living with the virus.”